Each is 13/16" with airplane or pilot against color background. Set was produced by Greenduck Co. Chicago in the the 1930s and each button is numbered. This complete set comes on an 8.5x11" stiff paper sheet divided into a grid and hand numbered to match the button number. This was the Hake Collection master set built over many years with constant upgrading as we acquired buttons in this set and these particular buttons are all NM to Mint with only the most minor exceptions, in particular some near microscopic craze lines on button #20 showing the "China Clipper." The first two buttons are captioned "Early Plane 'Pusher' Type" and "Dr. Rumpler's Taube German 1911." Other famous planes and pilots include: "Van Richthofen's Fighter, Ford Tri-motor, Douglas DC-2, Navy "Hell Diver", Wiley Post's "Winnie Mae", Famed Wright Bros' 'Pusher' Plane" as well as portraits of Orville Wright, Glenn Curtiss, Eddie Rickenbacker, Charles Lindbergh, Capt. Frank Hawks, Jimmy Mattern, Roscoe Turner, Howard Hughes, and the set concludes with five female pilots including Amelia Earhart Putnam. A wonderful set in NM to Mint condition. Comes with Hake's COA.